@@ -150,6 +150,16 @@ instanceTypeError"You can't compare functions for equality"=>Eq(a -> b)
> If that's inaccessible code and an error, they can't do this.
I don't think it will be so bad to write
instanceTypeError"You can't compare functions for equality"=>Eq(a -> b)where(==)= undefined
> I see no reason to complicate the compiler for this.
1. Relatedly, when definition an instance with a `TypeError` constraint, what should users write in the body? Leaving it empty causes warnings, but anything written in there would never be called. *Lennart*: See above.
1. Do we support `foo :: TypeError (Text "") -> TypeError (Text ""); foo = id`? I don't have a strong feeling one way or the other, but it would be nice to have this specified. *Lennart*: I would expect this to result in a type error at some point. If, after typechecking, there are any residual `TypeError` occurrences in types then something has gone wrong.